Egressing circuitry and other signal transmission media out of a confined space presents several issues. Interposing probes are often used in confined space in connection with target systems designed to probe electronic devices such as microprocessors. One alternative is to egress signals by edge mounting rigid PC boards to each other. Another solution is to laminate flex PCB to rigid PC board material in a multi-layer stack and then punch vias through the flex to connect the various layers. Still another alternative is to use flexible circuit material soldered to rigid PC board material and egress signal out at a right angle with a minimum bend radius. Yet another solution is to terminate a controlled impedance media to a paddle card, which is the connected to a flexible circuit via connector.
These prior alternatives do not generally allow a user to egress flexible circuitry and other signal transmission media out of a confined space at a minimum angle of ninety degrees. Accordingly, use of prior alternatives does not allow the most efficient use of PC board space due to a target board designer""s need to allow space for component placement.
In addition, reliability and life of the egression media is sacrificed by the prior alternatives. When flex egress is done at a right angle with a minimum bend radius, it puts stress on the individual traces of flex circuit or the dielectric of individually shielded transmission lines, especially if the user flexes a probe beyond the minimum bend radius.
The present invention provides for edge mounting to rigid board material allowing egress of flexible circuitry and other signal transmission media out of a confined space at a minimum angle of ninety degrees. This allows target board designers to place components in a much denser configuration. This also gives more flexibility to the board designer and the probe designer. Edge mounting technology allows the designer of a processor probe to egress flexible signal transmission media with minimum real estate utilized on the board.
The present invention also provides for greatly increased reliability and life of flexible media by edge mounting flex and other transmission media. Using edge mounting technology in accordance with the present invention, a minimum bend radius is locked in, relieving the stress on the media that would otherwise be experienced in a flex bend up design. Edge mounting in accordance with the invention provides a built in stress relief for the flexible transmission media. Instead of being required to bend the media at a minimum radius to egress signals from an interstitial array, the solder connections of the media to rigid piece provides a built in stress relief while creating a minimum bend radius egress of the media in the vertical (Z axis) direction.
The present invention also provides for increased signal integrity of probed signals by decreasing the electrical length that each signal must travel. By eliminating the bend radius, the overall length of the flexible portion of the probe can be reduced.